660MW电站锅炉二次高温再热蒸汽管道P92材料老化原因分析

Analysis of P92 Material Aging of 660MW Power Plant Boiler Secondary High Temperature Reheat Steam Pipe

通过化学成分分析、硬度分析、金相组织分析,对某电厂660MW电站锅炉二次高温再热蒸汽管道P92材料老化原因进行了综合分析。结果表明,材料老化的原因是热处理温度控制不当以及回火温度过高而使组织由马氏体分散生成δ-铁素体+碳化物所致。

The chemical composition, hardness, microstructure were investigated, and the reasons of P92 material aging of 660MW power plant boiler secondary high temperature reheat steam pipe were analyzed. The results show that the reasons of the material aging are the improper temperature control and high tempering temperature during the heat-treatment which make the structure of the tissue is distributed by the martensite to produce the δ-ferrite and carbide.